You yourself mentioned there were additional reasons 'lumped in' that I imagine answers your own question. I have to say I'm a little baffled by the tone of th

You yourself mentioned there were additional reasons 'lumped in' that I imagine answers your own question. I have to say I'm a little baffled by the tone of this response. It feels to me like you're implying physicists, in the general sense, came up with a hypothesis of dark matter to explain an observation, and then for no particular reason kept the idea of dark matter even after getting rid of any reason to continue to need dark matter to explain anything. As if the entire scientific community simply forgot to get rid of a particularly intuitive hypothesis after it was no longer useful, and the only people to recognize this are random folks on the internet. I'm no stranger to being suspicious or doubtful about authorities in general, and academia in particular, but I can't imagine putting forth the idea that nobody in the scientific community has never simply considered dark matter might not exist. It's just not a plausible situation, particularly considering how many lay folk have trouble with the idea. I'm sure every single astrophysicist has been confronted with this kind of question multiple times. And yet dark matter remains. That should say something about the current state of our observations, and how much dark matter is needed to explain them.